What does "sized" mean?

1. (having a specific size) having a particular size; you almost always use this with another word like 'small', 'medium', or 'life'. 2. (sized up) to have looked at someone or something carefully to form an opinion.

Is it correct to say "It was a medium size box."?

No — say "It was a medium-sized box.". When using the size as an adjective before a noun, use the '-ed' form and a hyphen.

sized

adj. · v.

US //ˈsaɪzd// UK //sˈaɪzd// sized

1 having a specific size (adj.)
B2 Upper Intermediate

having a particular size; you almost always use this with another word like 'small', 'medium', or 'life'.

having a specified dimension or magnitude. This form is typically non-gradable and functions as a combining form in compound adjectives.

Example

The hotel room was a decent-sized space with a view of the park.

Example

The laboratory was equipped with several medium-sized centrifuges, each calibrated for high-speed separation of chemical compounds.
- dimensioned
- proportioned
Pitfall

It was a medium size box.

It was a medium-sized box.

When using the size as an adjective before a noun, use the '-ed' form and a hyphen.
2 sized up (v.)
B2 Upper Intermediate Informal

to have looked at someone or something carefully to form an opinion.

the past tense of the phrasal verb 'size up', meaning to have made an assessment or judgment of a person or situation.

Example

The two boxers sized each other up before the fight began.

Example

The manager sized up the new recruits during the orientation, looking for those who demonstrated natural leadership qualities.
- evaluated
- assessed
- judged

Origin

From size + -ed.

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

Last updated June 19, 2026